A city on two wheels

At six in the evening, the crossroads at the edge of Hanoi's Old Quarter becomes a slow river of headlights. Motorbikes ease through streets that were laid out for carts and pedestrians, weaving around one another with a calm that looks, from the pavement, almost rehearsed. Mrs Lan, who sells cut flowers from a basket strapped to the back of her twenty-year-old Honda, has worked these streets since her daughter was a baby. "This bike is my shop, my van and my daughter's school bus," she says. "Without it, I sell nothing."

There are roughly seven million motorbikes registered in the capital, and for most families they are far more than a way of getting around. That versatility is what makes the city's latest plans so contentious. In winter, Hanoi's air regularly ranks among the most polluted in the region. To tackle it, the authorities have announced that petrol motorbikes will be phased out of the inner districts, starting with the area inside the innermost ring road. Exhaust from old, poorly maintained engines is one of several sources of the grey haze that settles over Hanoi each winter. Electric models, meanwhile, are getting cheaper every year.

For vendors like Mrs Lan, the arithmetic is unforgiving. A new electric bike would cost her several months of takings, and the room she rents has a single socket that she shares with a rice cooker and a fan. "They tell me it will be cheaper to run," she says. "First I need the money to buy it." Transport researchers point out that buses, despite recent improvements, still do not reach many of the narrow alleys where people actually live. Unless that gap is filled, a ban could push the poorest residents further from the customers and jobs they rely on.

Other places have made the switch without bringing daily life to a halt, though rarely quickly. In Taiwan, government subsidies for electric scooters arrived alongside a dense network of battery-swap stations, where riders exchange a flat battery for a charged one in seconds. Several Chinese cities restricted petrol motorbikes from the 1990s onwards, and in many of them cheap electric bikes soon took their place. What these cases have in common is the order of events. The new options were in place before the old one was taken away.

Few people in the Old Quarter quarrel with the goal. Mrs Lan complains about the winter haze as much as anyone, and her daughter coughs through most of December. Her questions are practical ones. When the rule reaches her street, will there be a bus that stops nearby, a charging point she can use and a loan she can afford? The answers to those questions, more than the date printed on the regulation, will decide whether Hanoi's riders see the change as progress or as one more cost they have to carry.